Multiclass Mlppp Configuration Guidelines; Multiclass Mlppp Traffic Classes Overview - Juniper JUNOSE 11.1.X - LINK LAYER CONFIGURATION 4-7-2010 Configuration Manual

JUNOSe 11.1.x Link Layer Configuration Guide
On MLPPP bundles that consist of physical links of different types, MLPPP does not
guarantee the receipt of high-priority data packets in sequence. Multiclass MLPPP
enables you to fragment data packets of different priorities into multiple multilink
classes. Because every multilink class has its own transmit and receive context, data
packets of each class are received in the same sequence they were transmitted.
With multiclass MLPPP, data packets of each multilink class are encapsulated in an
MLPPP header. The sequence numbers of each class are also embedded within the
header before transmission. The receiving peer processes each class independently
and uses the sequence numbers in the MLPPP header to internally reorder and
reassemble packets in the desired sequence.

Multiclass MLPPP Configuration Guidelines

Use the following guidelines while configuring multiclass MLPPP:
Related Topics

Multiclass MLPPP Traffic Classes Overview

A traffic class is a system-wide collection of buffers, queues, and bandwidth that you
can allocate to provide a defined level of service to packets in the traffic class. With
multiclass MLPPP, high-priority and low-priority data packets are fragmented into
their respective QoS traffic classes before being transmitted. The QoS traffic classes
are each mapped to a separate multilink class.
The major benefits of mapping traffic classes to multilink classes are:
The default traffic class is the best-effort traffic class. You can configure fragmentation
and reassembly on all traffic classes. Any packet without a
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Multiclass MLPPP Traffic Classes Overview
Configure multiclass MLPPP on each link in the MLPPP bundle. If any link is not
configured, the receiving peer might prevent the mismatched link from joining
the bundle.
The first link to join a bundle determines whether multiclass MLPPP is configured
on the bundle. All subsequent links must also negotiate the same multiclass
MLPPP parameters as that of the first link. The configuration for each link in a
bundle is identical.
JUNOSe Link Layer Configuration Guide, Chapter 9, Configuring Multilink PPP
Configuring Multiclass MLPPP on page 352
The multiclass MLPPP feature supports the mapping of up to eight traffic classes.
You can fragment data packets into a maximum of eight different priorities of
traffic classes.
Classes of higher-priority can be interleaved between classes of lower priority,
which reduces transmission latency.
Every multilink class has its own transmit and receive context. These contexts
ensure that data packets of higher priority traffic classes are received in the order
they were transmitted.